Metal-carbon compositions

ABSTRACT

A gold-carbon compound that is a reaction product of gold and carbon, wherein the gold and the carbon form a single phase material that is meltable. The compound is one in which the carbon does not phase separate from the gold when the single phase material is heated to a melting temperature.

RELATED REFERENCES

This application is a divisional of U.S. application Ser. No.13/021,271, filed Feb. 4, 2011, which claims the benefit of U.S.provisional application No. 61/301,382, filed Feb. 4, 2010, U.S.provisional application No. 61/301,398, filed Feb. 4, 2010, U.S.provisional application No. 61/301,412, filed Feb. 4, 2010, U.S.provisional application 61/301,432, filed Feb. 4, 2010, and U.S.provisional application No. 61/301,446, filed Feb. 4, 2010.

FIELD

The present application relates to compounds and/or compositions thatinclude a metal and carbon that are formed into a single phase materialand, more particularly, to gold-carbon, silver-carbon, tin-carbon,zinc-carbon, and lead-carbon compositions wherein the carbon does notphase separate from the metal when the metal-carbon compositions aremelted or re-melted.

BACKGROUND

Gold is highly resistant to oxidation in air and water, and isrelatively resistant to corrosive agents. Gold alloys, such as goldalloys of silver and copper, also present desired properties.Nonetheless, those skilled in the art continue to seek to improve uponthe properties of gold.

Silver is high prized for its aesthetic, chemical and physicalproperties. For example, silver is highly electrically and thermallyconductive. However, silver's high cost and propensity to tarnish whenexposed to atmospheric conditions has limited its use in industrialapplications. Therefore, those skilled in the art continue to attempt toenhance the physical and chemical properties of silver.

Tin is a malleable, corrosion-resistant metal that is useful in a widevariety of applications. Nonetheless, those skilled in the art continueto attempt to enhance the physical and chemical properties of tin.

Zinc is a brittle and reactive metal that is used in a wide variety ofapplications. Nonetheless, those skilled in the art continue to attemptto enhance the physical and chemical properties of zinc.

Lead is a malleable and corrosion-resistant reactive metal that is usedin a wide variety of applications. Nonetheless, those skilled in the artcontinue to attempt to enhance the physical and chemical properties oflead.

SUMMARY

In one aspect, the disclosed metal-carbon composition may include goldand carbon, silver and carbon, lead and carbon, zinc and carbon, or tinand carbon, wherein the metal and the carbon form a single phasematerial and the carbon does not phase separate from the metal when thematerial is heated to a melting temperature.

In another aspect, the disclosed metal-carbon composition may consistessentially of the metal and the carbon. The metal and the carbon form asingle phase material, where the carbon does not phase separate from themetal when the material is heated to a melting temperature. Themetal-carbon composition may be a gold and carbon, silver and carbon,lead and carbon, zinc and carbon, or tin and carbon.

Herein, the metal in the metal-carbon composition is gold.

In another aspect, gold-carbon compounds are disclosed that are areaction product of gold and carbon that is a single phase material. Thesingle phase material is meltable, and the carbon does not phaseseparate from the gold when the single phase material is subsequentlyre-melted.

Other aspects of the disclosed gold-carbon composition will becomeapparent from the following description and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an image of a fracture surface of the silver-carboncomposition formed according to Example Ag-3 that has been fractured bybending.

DETAILED DESCRIPTION

Metal-based compounds and/or compositions that have carbon incorporatedtherein are disclosed. The compounds or compositions are a metal-carbonmaterial that form a single phase material, and in such a way that thecarbon does not phase separate from the metal when the material ismelted. The metal may be gold, silver, tin, lead, or zinc. Carbon can beincorporated into any of these metals by melting the metal, mixing thecarbon into the molten metal and, while mixing, applying a current ofsufficient amperage to the molten mixture such that the carbon becomesincorporated into the metal, thereby forming a single phase metal-carbonmaterial. It is important that the current is applied while mixing thecarbon into the molten metal. The current is preferably DC current, butis not necessarily limited thereto. The current may be appliedintermittently in periodic or non-periodic increments. For example, thecurrent may optionally be applied as one pulse per second, one pulse pertwo seconds, one pulse per three seconds, one pulse per four seconds,one pulse per five seconds, one pulse per six seconds, one pulse perseven seconds, one pulse per eight seconds, one pulse per nine seconds,one pulse per ten seconds and combinations or varying sequences thereof.Intermittent application of the current may be advantageous to preservethe life of the equipment and it can save on energy consumption costs.

The current may be provided using an arc welder. The arc welder shouldinclude an electrode that will not melt in the metal, such as a carbonelectrode. In carrying out the method, it may be appropriate toelectrically couple the container housing the molten metal to groundbefore applying the current. Alternately, the positive and negativeelectrode can be placed generally within about 2 to 7 inches of oneanother, which increases the current density and as a result increasesthe bonding rate of the metal and carbon.

As used herein, the term “phase” means a distinct state of matter thatis identical in chemical composition and physical state and isdiscernable by the naked eye or using basic microscopes (e.g., at mostabout 10,000 times magnification). Therefore, a material appearing as asingle phase to the naked eye, but showing two distinct phases whenviewed on the nano-scale should not be construed as having two phases.

As used herein, the phrase “single phase” means that the elements makingup the material are bonded together such that the material is in onedistinct phase.

While the exact chemical structure of the disclosed metal-carbonmaterial is currently not known, without being limited to any particulartheory, it is currently believed that the steps of mixing and applyingelectrical energy result in the formation of chemical bonds between themetal and carbon atoms, thereby rendering the disclosed metal-carboncompositions unique vis-à-vis known metal-carbon composites andsolutions of metal and carbon. Without being bound by theory, it isbelieved that the carbon is covalently bonded to the metal in themetal-carbon materials disclosed herein. The bonds may be single,double, and triple covalent bonds or combinations thereof, but it isbelieved, again without being bound by theory, that the bonds are mostlikely double or triple bonds. Accordingly, the covalent bonds formedbetween the metal and the carbon are not broken, i.e., the carbon doesnot separate from the metal, merely by melting the resulting singlephase metal-carbon material or “re-melting” as described above.Furthermore, without being limited to any particular theory, it isbelieved that the disclosed metal-carbon material is a nanocompositematerial and, as evidenced by the Examples herein, the amount ofelectrical energy (e.g., the current) applied to form the disclosedmetal-carbon composition initiates an endothermic chemical reaction.

The disclosed metal-carbon material does not phase separate, afterformation, when re-melted by heating the material to a meltingtemperature (i.e., a temperature at or above a temperature at which theresulting metal-carbon material begins to melt or becomes non-solid).Thus, the metal-carbon material is a single phase composition. For eachof the five metal-carbon materials disclosed herein stable compositionsof matter were made that do not phase separate upon subsequentre-melting. Furthermore, the metal-carbon material remains intact as avapor, as the same chemical composition, as evidenced by magnetronsputtering tests. Samples of the various metal-carbon materials weresputtered and upon sputtering were deposited as a thin film on asubstrate and retained the electrical resistivity of the bulk materialbeing sputtered. If the metal and carbon were not bonded together, thenit would have been expected from electrical engineering principles andphysics that the electrical resistivity would be roughly two orders ofmagnitude higher. This did not occur.

The carbon in the disclosed metal-carbon compound may be obtained fromany carbonaceous material capable of producing the disclosedmetal-carbon composition. Non-limiting examples include high surfacearea carbons, such as activated carbons, and functionalized orcompatibilized carbons (as familiar to the metal and plasticsindustries). A suitable non-limiting example of an activated carbon is apowdered activated carbon available under the trade name WPH®-Mavailable from Calgon Carbon Corporation of Pittsburgh, Pa.Functionalized carbons may be those that include another metal orsubstance to increase the solubility or other property of the carbonrelative to the metal the carbon is to be reacted with, as disclosedherein. In one aspect, the carbon may be functionalized with nickel,copper, aluminum, iron, or silicon using known techniques.

In one embodiment, the metal in the metal-carbon compound is gold. Thegold may be any gold or gold alloy capable of producing the disclosedgold-carbon compound. Those skilled in the art will appreciate that theselection of gold may be dictated by the intended application of theresulting gold-carbon compound. In one embodiment, the gold is 0.9999gold.

In another embodiment, the metal in the metal-carbon compound is silver.The silver may be any silver or silver alloy capable of producing thedisclosed silver-carbon compound. Those skilled in the art willappreciate that the selection of silver may be dictated by the intendedapplication of the resulting silver-carbon compound. In one embodiment,the silver is 0.9995 silver. In one embodiment, the silver is sterlingsilver.

In another embodiment, the metal in the metal-carbon compound is tin.The tin may be any tin or tin alloy capable of producing the disclosedtin-carbon compound. Those skilled in the art will appreciate that theselection of tin may be dictated by the intended application of theresulting tin-carbon compound. In one embodiment, the tin is 0.999 tin.In one embodiment, the tin is an alloy such as a bronze, a tin solder,or a tin pewter.

In another embodiment, the metal in the metal-carbon compound is lead.The lead may be any lead or lead alloy capable of producing thedisclosed lead-carbon compound. Those skilled in the art will appreciatethat the selection of lead may be dictated by the intended applicationof the resulting lead-carbon compound. In one embodiment, the lead is0.999 lead. In one embodiment, the lead is an alloy such as a tin solderor a tin pewter, which both contain lead.

In another embodiment, the metal in the metal-carbon compound is zinc.The zinc may be any zinc or zinc alloy capable of producing thedisclosed zinc-carbon compound. Those skilled in the art will appreciatethat the selection of zinc may be dictated by the intended applicationof the resulting zinc-carbon compound. In one embodiment, the zinc is0.999 zinc. In one embodiment, the zinc is an alloy such as a brass.

In another aspect, the single phase metal-carbon material may beincluded in a composition or may be considered a composition because ofthe presence of other impurities or other alloying elements present inthe metal and/or metal alloy.

Similar to metal matrix composites, which include material at least twoconstituent parts, one being a metal, the metal-carbon compositionsdisclosed herein may be used to form metal-carbon matrix composites. Theother material included in the metal-carbon matrix composite may be adifferent metal or another material, such as but not limited to aceramic, glass, carbon flake, fiber, mat, or other form. Themetal-carbon matrix composites may be manufactured or formed using knownand similarly adapted techniques to those for metal matrix composites.

In one aspect, the disclosed metal-carbon compound or composition maycomprise at least about 0.01 percent by weight carbon. In anotheraspect, the disclosed metal-carbon compound or composition may compriseat least about 0.1 percent by weight carbon. In another aspect, thedisclosed metal-carbon compound composition may comprise at least about1 percent by weight carbon. In another aspect, the disclosedmetal-carbon compound or composition may comprise at least about 5percent by weight carbon. In another aspect, the disclosed metal-carboncompound or composition may comprise at least about 10 percent by weightcarbon. In yet another aspect, the disclosed metal-carbon compound orcomposition may comprise at least about 20 percent by weight carbon.

In another aspect, the disclosed metal-carbon compound or compositionmay comprise a maximum of 1%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, or 40%by weight carbon. In one embodiment, the metal-carbon compound orcomposition may have the maximum percent by weight carbon customized toprovide particular properties thereto.

The percent by weight carbon present in the compound or composition maychange the thermal conductivity, ductility, electrical conductivity,corrosion resistance, oxidation, formability, strength performance,and/or other physical or chemical properties. In the silver-carboncompound or composition it has been determined that increased carboncontent enhances the ductility of the material. However, surprisingly,the zinc-carbon compound or composition has decreased ductility withincreased carbon content. Accordingly, the customization of the physicaland chemical properties of the metal-carbon compounds or compositions isnot uniform across the metals selected and requires careful research andanalysis.

The formation of the metal-carbon composition may result in a materialhaving at least one significantly different property than the metal. Forexample, the silver-carbon compositions and the copper-carboncompositions may not have the antimicrobial property of silver andcopper, and the lead-carbon compositions may not have the toxicity oflead.

In one embodiment, the carbon is present in the metal-carbon material asabout 0.01 to about 40 percent by weight of the composition. In anotherembodiment, the carbon is present in the metal-carbon material as about1 to about 70 percent by weight of the composition.

Accordingly, the disclosed metal-carbon compositions may be formed bycombining certain carbonaceous materials with the selected metal to forma single phase material, wherein the carbon from the carbonaceousmaterial does not phase separate from the metal when the single phasematerial is cooled and subsequently re-melted. The metal-carboncompositions may be used in numerous applications as a replacement formore traditional metals or metal alloys and/or plastics and inhereinafter developed technologies and applications.

EXAMPLES Gold Example Au-1

A graphite crucible (electrically coupled to ground) having a volume of65 in³ was positioned in a Kerr brand electric induction furnace. Thecrucible was charged with 151 grams of 99.99 percent plus purity gold.The gold was heated to a temperature of 2000° F.

The agitator end of a rotary mixer was inserted into the molten gold andthe rotary mixer was actuated to form a vortex. While mixing, 7.5 gramsof powdered activated carbon was introduced to the molten gold using acustom built feeding unit. The powdered activated carbon used was WPH®-Mpowdered activated carbon, available from Calgon Carbon Corporation ofPittsburgh, Pa.

A carbon electrode affixed to an arc welder was positioned in thecrucible. The arc welder was a Pro-Mig 135 arc welder obtained from TheLincoln Electric Company of Cleveland, Ohio. Immediately after addingthe powdered activated carbon to the molten gold, and while continuingto mix the carbon into the molten gold, the arc welder was actuated(setting: D) to supply electric current through the molten gold andcarbon mixture. A graphite electrode was attached to the welding rod tosupply the current to the melt, which was applied intermittently asappropriate for the arc welder and the electrical power circuit. Thetemperature of the material rapidly dipped to 1700° F. and the materialsolidified, suggesting an endothermic reaction had occurred.

Subsequently, the material was reheated to 2048° F. and an additional7.5 grams of powdered activated carbon was added and the electriccurrent was applied, resulting in a temperature drop to 1948° F. Thematerial was reheated to 2048° F. and an additional 7.5 grams ofpowdered activated carbon was added and the electric current wasapplied, resulting in a temperature drop to 1957° F. The material wasreheated to 2048° F. and an additional 7.5 grams of powdered activatedcarbon was added and the electric current was applied, resulting in atemperature drop to 1981° F. The material was reheated to 2048° F. andan additional 7.5 grams of powdered activated carbon was added and theelectric current was applied, resulting in a temperature drop to 1970°F.

After cooling, the gold-carbon composition was observed by the naked eyeto exist in a single phase. The material was noted to have cooledrapidly. The cooled gold-carbon composition was then re-melted byheating to 2048° F., and no phase separation was observed.

Furthermore, testing showed that the gold-carbon composition hadimproved thermal conductivity and fracture toughness when rolled into athin film.

Silver Example Ag-1

A graphite crucible (electrically coupled to ground) having a volume of65 in³ was positioned in a Kerr brand electric induction furnace. Thecrucible was charged with 15 grams of 99.99 percent plus purity silver.The silver was heated to a temperature of 1860° F.

The agitator end of a rotary mixer was inserted into the molten silverand the rotary mixer was actuated to form a vortex. While mixing, 30grams of powdered activated carbon (no clumps) was introduced to themolten silver using a custom built feeding unit. The powdered activatedcarbon used was WPH®-M powdered activated carbon, available from CalgonCarbon Corporation of Pittsburgh, Pa.

A carbon electrode affixed to an arc welder was positioned in thecrucible. The arc welder was a Pro-Mig 135 arc welder obtained from TheLincoln Electric Company of Cleveland, Ohio. Immediately after addingthe powdered activated carbon to the molten silver, and while continuingto mix the carbon into the molten silver, the arc welder was actuated(setting: A-1) to supply electric current through the molten silver andcarbon mixture. A graphite electrode was attached to the welding rod tosupply the current to the melt, which was applied intermittently asappropriate for the arc welder and the electrical power circuit. Then,the molten material was poured into a holding vessel to cool.

After cooling, the silver-carbon composition was observed by the nakedeye to exist in a single phase. The material was noted to have cooledrapidly. The cooled silver-carbon composition was then re-melted in thecrucible by heating to 2048° F., and no phase separation was observed.

Furthermore, testing showed that the silver-carbon composition wasresistant to tarnishing, even in the presence of hydrogen sulfide, andhad improved thermal conductivity and fracture toughness when rolledinto a thin film. Grain orientation and significantly reduced grain sizewere also observed.

Example Ag-2

Using the same experimental set-up described in Example Ag-1, 137 gramsof 99.99 percent plus purity silver was heated to a temperature of 2000°F. and 7.5 grams of powdered activated carbon was added. After applyingthe electric current, the temperature of the material rapidly dipped to1670° F., suggesting an endothermic reaction had occurred. The materialwas reheated to 2000° F. and additional powdered activated carbon (7.5grams) was added and, while mixing, the material was once again pulsedwith electric current.

After cooling, the silver-carbon composition weighed 151 grams and wasobserved by the naked eye to exist in a single phase. The material wasnoted to have cooled rapidly. The cooled silver-carbon composition wasthen re-melted by heating to 2048° F., and no phase separation wasobserved.

Furthermore, a bar formed from the resulting silver-carbon compositionwas surprisingly resistant to fracturing after repeated bending,indicating significantly enhanced fracture toughness.

Example Ag-3

Using the same experimental set-up described in Example Ag-1, 1100 gramsof 99.99 percent plus purity silver was heated to a temperature of 1880°F. and an unknown quantity of powdered activated carbon was added and anelectric current was applied to the mixture. The temperature of thematerial was observed to rapidly dip to 1700° F. The material wasreheated to 1920° F. and a second unknown quantity of powdered activatedcarbon was added and the material was once again pulsed with electriccurrent.

The resulting material was poured in a mold and left in a kilnovernight. The following day, the cooled silver-carbon composition wasremoved from the mold and bent until fractured. The fractured structure,as shown in FIG. 1, has an unusual amount of orientation.

Tin Example Sn-1

A graphite crucible (electrically coupled to ground) having a volume of65 in³ was positioned in a Kerr brand electric induction furnace. Thecrucible was charged with 90 grams of 99.9 percent pure tin. The tin washeated to a temperature of 550° F.

The agitator end of a rotary mixer was inserted into the molten tin andthe rotary mixer was actuated to form a vortex. While mixing, anunmeasured quantity of powdered activated carbon was introduced to themolten tin using a custom built feeding unit. The powdered activatedcarbon used was WPH®-M powdered activated carbon, available from CalgonCarbon Corporation of Pittsburgh, Pa.

A carbon electrode affixed to an arc welder was positioned in thecrucible. The arc welder was a Pro-Mig 135 arc welder obtained from TheLincoln Electric Company of Cleveland, Ohio. Immediately after addingthe powdered activated carbon to the molten tin, and while continuing tomix the carbon into the molten tin, the arc welder was actuated(setting: A-1) to supply electric current through the molten tin andcarbon mixture. A graphite electrode was attached to the welding rod tosupply the current to the melt, which was applied intermittently asappropriate for the arc welder and the electrical power circuit. Aslight temperature increase was observed and the tin-carbon compositionappeared as a viscous gel.

After cooling, the tin-carbon composition was observed by the naked eyeto exist in a single phase. The material was noted to have cooledrapidly. The cooled tin-carbon composition was then re-melted by heatingto 1000° F., and no phase separation was observed.

Furthermore, the tin-carbon composition appeared to be more putty-likethan tin metal while below the melting temperature. The resultingtin-carbon material underwent a color change from gray to a gold-tintedcolor. Testing showed that the tin-carbon composition had a reducedgrain size, increased thermal conductivity and improved fracturetoughness.

Example Sn-2

Using the same experimental set-up described in Example Sn-1, 238 gramsof 99.9 percent pure tin was heated to a temperature of 604° F. and anunmeasured quantity of powdered activated carbon was added. Afterapplying the electric current (setting: D), the material gelled and thetemperature of the material slightly increased. The material was heatedto 700° F. and additional powdered activated carbon was added and, whilemixing, was once again pulsed with electric current. Finally, thematerial was heated to 800° F. and additional powdered activated carbonwas added and the mixture was once again pulsed with electric current.

After cooling, the tin-carbon composition was evaluated and had the sameproperties described above in Example Sn-1. The material was noted tohave cooled rapidly.

Zinc Example Zn-1

A graphite crucible (electrically coupled to ground) having a volume of65 in³ was positioned in a Kerr brand electric induction furnace. Thecrucible was charged with 213 grams of 99.9 percent pure zinc. The zincwas heated to a temperature of 893° F.

The agitator end of a rotary mixer was inserted into the molten zinc andthe rotary mixer was actuated to form a vortex. While mixing, anunmeasured quantity of powdered activated carbon was introduced to themolten zinc using a custom built feeding unit. The powdered activatedcarbon used was WPH®-M powdered activated carbon, available from CalgonCarbon Corporation of Pittsburgh, Pa.

A carbon electrode affixed to an arc welder was positioned in thecrucible. The arc welder was a Pro-Mig 135 arc welder obtained from TheLincoln Electric Company of Cleveland, Ohio. Immediately after addingthe powdered activated carbon to the molten zinc, and while continuingto mix the carbon into the molten zinc, the arc welder was actuated(setting: D) to supply electric current through the molten zinc andcarbon mixture. A graphite electrode was attached to the welding rod tosupply the current to the melt, which was applied intermittently asappropriate for the arc welder and the electrical power circuit. Thetemperature of the material increased to 917° F. and the materialappeared as a viscous gel. The dross was removed and the material wasallowed to slightly cool before reheating the material to 888° F., atwhich point the material remained gel-like despite being at atemperature 100° F. greater than the melting temperature of zinc.

After cooling, the zinc-carbon composition was observed by the naked eyeto exist in a single phase. The material was noted to have cooledrapidly. The cooled zinc-carbon composition was then re-melted byheating to greater than 1000° F., and no phase separation was observed.

Testing showed that the zinc-carbon composition had a significantlyreduced grain size, increased thermal conductivity and increasedreflectivity. No enhancement in ductility or fracture toughness wasobserved.

Example Zn-2

Using the same experimental set-up described in Example Zn-1, 622 gramsof 99.9 percent pure zinc was heated to a temperature of 900° F. and anunmeasured quantity of powdered activated carbon was added to the moltenzinc. After applying the electric current (setting: D), the materialgelled and the temperature of the material remained at about 900° F. Thematerial remained gel-like after being heated to 987° F., but turned avery shinny, yellowish-orange color after being heated to 1087° F. Withthe material at 1087° F., additional powdered activated carbon was addedand, while mixing, was once again pulsed with electric current, afterwhich the material was allowed to cool. The material was noted to havecooled rapidly.

The resulting zinc-carbon composition was evaluated and had the sameproperties described above in Example Zn-1.

Lead Example Pb-1

A graphite crucible (electrically coupled to ground) having a volume of65 in³ was positioned in a Kerr brand electric induction furnace. Thecrucible was charged with 201 grams of 99.9 percent pure lead. The leadwas heated to a temperature of 721° F.

The agitator end of a rotary mixer was inserted into the molten lead andthe rotary mixer was actuated to form a vortex. While mixing, anunmeasured quantity of powdered activated carbon was introduced to themolten lead using a custom built feeding unit. The powdered activatedcarbon used was WPH®-M powdered activated carbon, available from CalgonCarbon Corporation of Pittsburgh, Pa.

A carbon electrode affixed to an arc welder was positioned in thecrucible. The arc welder was a Pro-Mig 135 arc welder obtained from TheLincoln Electric Company of Cleveland, Ohio. Immediately after addingthe powdered activated carbon to the molten lead, and while continuingto mix the carbon into the molten lead, the arc welder was actuated tosupply electric current through the molten lead and carbon mixture. Agraphite electrode was attached to the welding rod to supply the currentto the melt, which was applied intermittently as appropriate for the arcwelder and the electrical power circuit. The temperature of the materialincreased to 821° F. The material was cooled to 784° F. and poured intomolds, after which the material rapidly cooled to room temperature. Thematerial did not pour like ordinary molten lead and exhibited unusuallayering in the mold, resembling a thermoplastic. It was also noted thatthe material cooled rapidly.

The lead-carbon composition was observed by the naked eye to exist in asingle phase. The cooled lead-carbon composition was then re-melted byheating to greater than 1000° F., and no phase separation was observed.

Although various aspects of the disclosed metal-carbon compositions havebeen described, modifications may occur to those skilled in the art uponreading the specification. The present application includes suchmodifications and is limited only by the scope of the claims.

What is claimed is:
 1. A metal-carbon composition comprising: gold andcarbon, wherein the gold and the carbon form a single phase materialformed by mixing carbon into the gold while molten under conditions thatchemically react the gold and the carbon, and wherein the single phasematerial is meltable and the carbon does not phase separate from thegold when the single phase material is subsequently re-melted.
 2. Themetal-carbon composition of claim 1 wherein the gold is from a goldalloy, the gold is bonded to the carbon and the composition includes theremaining alloying elements or impurities of the gold alloy.
 3. Themetal-carbon composition of claim 1 wherein the carbon comprises about0.01 to about 40 percent by weight of the material.
 4. The metal-carboncomposition of claim 1 wherein the carbon comprises at least about 1percent by weight of the material.
 5. The metal-carbon composition ofclaim 1 wherein the carbon comprises at least about 5 percent by weightof the material.
 6. The metal-carbon composition of claim 1 wherein thecarbon comprises at most about 10 percent by weight of the material. 7.The metal-carbon composition of claim 1 wherein the carbon comprises atmost about 25 percent by weight of the material.
 8. The metal-carboncomposition of claim 1 further comprising an additive that imparts achange to a physical or mechanical property of the composition.
 9. Ametal-carbon composition consisting essentially of gold and carbon,wherein the gold and the carbon form a single phase material formed bymixing carbon into the gold while molten under conditions thatchemically react the gold and the carbon, and wherein the single phasematerial is meltable and the carbon does not phase separate from thegold when the single phase material is subsequently re-melted.
 10. Themetal-carbon composition of claim 9 wherein the gold is from a goldalloy, the gold is bonded to the carbon and the composition includes theremaining alloying elements or impurities of the gold alloy.
 11. Themetal-carbon composition of claim 9 wherein the carbon comprises about0.01 to about 40 percent by weight of the material.
 12. The metal-carboncomposition of claim 9 wherein the carbon comprises at least about 1percent by weight of the material.
 13. The metal-carbon composition ofclaim 9 wherein the carbon comprises at least about 5 percent by weightof the material.
 14. The metal-carbon composition of claim 9 wherein thecarbon comprises at most about 10 percent by weight of the material. 15.The metal-carbon composition of claim 9 wherein the carbon comprises atmost about 25 percent by weight of the material.
 16. The metal-carboncomposition of claim 9 wherein the carbon is a high surface area carbon.17. The metal-carbon composition of claim 16 wherein the high surfacearea carbon is a powdered carbon.
 18. The metal-carbon composition ofclaim 1 wherein the carbon is a high surface area carbon.
 19. Themetal-carbon composition of claim 18 wherein the high surface areacarbon is a powdered carbon.
 20. A gold-carbon compound comprising: areaction product of gold and carbon that is a single phase material,wherein the single phase material is meltable, and the carbon does notphase separate from the gold when the single phase material issubsequently re-melted.